UNIVERSITY OF MALTA
THE MATRICULATION CERTIFICATE EXAMINATION
INTERMEDIATE LEVEL
BIOLOGY
May 2011
EXAMINERS’ REPORT
MATRICULATION AND SECONDARY EDUCATION
CERTIFICATE EXAMINATIONS BOARD
IM 05 Examiners’ Report: May 2011
Biology
Intermediate Level
May 2011
Part 1: Statistical Information
Table 1: Distribution of Grades awarded in May 2011
GRADE
Number
% of Total
A
B
22
8.37
C
55
20.91
D
73
27.76
E
46
17.49
F
28
10.65
Abs
20
7.60
19
7.22
Total
263
100
Part 2: Comments regarding candidate’s performance
Section A
Question 1: Cell structure
Most answers presented were correct. Typical mistakes observed included the presence of chloroplasts and a
cellulose cell wall in prokaryotic cells and the absence of ribosomes in prokaryotic cells.
Question 2: Nucleic acids
Q2.1: Most answers were correct, with candidates correctly distinguishing between deoxyribose and ribose.
Q2.2: Most answers were correct. Some candidates incorrectly suggested the presence of uracil in DNA.
Q2.3: Most answers were correct. However a significant percentage confused covalent bonds and hydrogen
bonds, resulting in an incorrect response.
Q2.4: Most answers were correct, with candidates generally correctly referring to DNA helicase as the enzyme
that unwinds DNA.
Q2.5: Generally correct answers were presented, however many candidates were unable to explain the role of
DNA polymerase in DNA replication clearly.
Question 3: Gaseous exchange
Q3.1: Most candidates defined gaseous exchange well.
Q3.2: In this part of the question, answers were often not awarded full marks as candidates did not clearly refer
to an increased rate of diffusion. Instead phrases such as ‘increases efficiency’ or ‘becomes more efficient’ were
used.
(a) Responses were generally correct. Some candidates however did not relate the large cumulative
surface area to an increased rate of diffusion.
(b) Most answers were incorrect. Candidates should note that diffusion does not occur faster in liquid
environments.
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IM 05 Examiners’ Report: May 2011
(c) Answers were generally correct. However a significant number of candidates did not relate the thin
nature of the alveolar epithelial wall to a short diffusion distance, thus leading to a faster rate of
diffusion.
(d) Most answers were incorrect. Only a few candidates linked the presence of a dense network of thinwalled capillaries to the maintenance of a high concentration gradient of respiratory gases. Instead
answers generally focused on the transport of a high concentration of oxygen.
Question 4: Immune system
Q4.1: Most candidates answered this question correctly.
Q4.2: Most candidates answered this question well. Yet, candidates often had difficulty in expressing themselves
in correct English.
Q4.3: Most candidates identified the role of mucous membranes correctly but often omitted the role of the skin
as a physical barrier to pathogens.
Question 5: Ecological interactions
Q5.1: Majority of candidates answered this question well.
Q5.2: Majority of candidates answered this question well and included examples of factors that influence the
carrying capacity of a habitat.
Q5.3: Majority of candidates answered this question well. Some, however found it difficult to express themselves
in correct English.
Q5.4: Most answers were incomplete. Candidates often explained correctly why the Carob Trees belong to
different populations but did not explain why they belong to the same species. Furthermore, some candidates
misunderstood the question and focused on speciation and geographical isolation.
Q5.5: Most answers were incorrect or incomplete. Frequently, reference to survival of the fittest was not linked
to natural selection and eventually evolution.
Question 6: Biotechnology
Majority of candidates presented correct answers. A common mistake that was notes was confusing the roles of
endonucleases with other enzymes, particularly DNA ligase.
Question 7: Photosynthesis (response rate 84%)
Q7.1: A number of candidates were unable to draw a clear biological diagram (wrong proportions and lack of
neatness), while there was a significant number of candidates who omitted important structures such as xylem
and phloem. The overall performance in labelling was good.
Q7.2: Most candidates completed this question correctly.
Q7.3: Most candidates were able to identify the correct environmental factors, but several were unable to
express their ideas on the effects of environmental factors on the rate of photosynthesis. Such descriptions could
have been easily expressed through the use of graph aiding the candidates to better communicate their ideas.
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IM 05 Examiners’ Report: May 2011
Q7.4: Almost all candidates were able to give a definition for primary producers but some were unable to link it to
food webs.
Question 8: Human impact on the environment (response rate 48%)
Q8.1: Most candidates were able to name a few changes that a habitat undergoes when it is degraded, but only a
few managed to score full marks.
Q8.2:
(a) Most candidates tackled this question correctly, and discussed it in view of land waste and also waste in
the marine environment (including sewage). However a number of candidates misinterpreted the
question and did not discuss waste disposal in relation to environment degradation, but rather discussed
processes of waste disposal.
(b) Some candidates did not link agriculture with habitat degradation. Moreover a large number of
candidates mixed up the effects of pesticides with the effects of artificial fertilizers, as they seemed
unable to distinguish between the two.
(c) In this question, several candidates confused global warming with ozone depletion. Moreover a good
number of candidates focused their discussion on global warming rather than describing other
environmental issues such as the production of other dangerous gases and acid rain.
(d) Some candidates described deforestation without linking it to environmental degradation, while other
candidates only discussed loss of trees in terms of loss of habitat.
Question 9: Nervous system (response rate 14%)
Q9.1: Some candidates did not show the general organization of the nervous system, but rather showed a
diagram of a neuron. However, on the whole, this question was answered correctly.
Q9.2: It was evident that some candidates were not familiar with the processes involved in the generation and
propagation of the nerve impulse. Additionally, many other candidates found it difficult to incorporate and
articulate the role of the channel proteins in their answer.
Q9.3: Many candidates showed poor understanding of the processes involved in the transmission of an impulse
from one neuron to another. Some candidates did not name the chemicals involved, while others did not make
use of correct biological terms. Some candidates made use of diagrams to better describe the processes
requested in this question.
Q9.4: Most candidates did name some effects of nicotine on the nervous system, but few managed to score full
marks.
Question 10: Taxonomy (response rate 36%)
Q10.1: Although most candidates seemed to know what Kingdoms are, only a few managed to fully explain the
term. In fact most candidates failed to indicate that it is the highest taxonomic group or that organisms within a
Kingdom have similar characteristics.
Q10.2: Most candidates were aware of the five kingdom system, but some did not identify the five Kingdoms,
while others included viruses as part of their list. However most of the candidates who identified the Kingdoms
were able to proceed with a good answer. The only concern here is about Kingdom Animalia, as several
candidates described this Kingdom as being only composed of vertebrates.
Question 11: Cell Cycle (response rate 17%)
Q11.1: Most candidates did not identify and discuss all the major stages in the cell cycle.
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IM 05 Examiners’ Report: May 2011
Q11.2: Most candidates were able to give a good description of the processes occurring during mitosis and
meiosis. Some candidates used diagrammatic representations of the processes involved, and this generally led ot
better answers. However, a number of candidates were unable to distinguish between chromosomes and
chromatids and others incorrectly identified meiosis 1 with mitosis.
Q11.3: Most candidates answered this question correctly, although some did not apparently understand the
question correctly and discussed genetic variation in terms of fertilization rather than as that occurring during
meiosis.
Chairperson
Board of Examiners
July 2011
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